The present invention relates to a transfer fixture and more particularly to a shaft seal unitized transfer fixture for the assembly of seal components and their transfer onto a shaft and into a unit to be sealed.
Mechanical face seal components, such as utilized in refrigeration compressors, generally consist of two units; a stator and a rotor which are ordinarily installed as separate components. A precise fit is required between the units and also between the seal assembly and the unit into which it is installed. In the case of a refrigeration compressor, a precision fit is required between the seal assembly and the plenum in which it is operated. The entrance of any foreign material, even of microscopic size, or a smudge from finger marks will inhibit optimum performance and establish a leak path. Leak paths occur primarily along the shaft, in the seal area between the elastomer and the rotating member which is in contact with the stator, or at the contact noses of the superfinished areas of the stator and rotor. The present invention aids in the assembly of the seal components and in the protection of the assembled seal until its installation into the mechanism to be sealed.
Among the objects of the present invention is the provision of a unitized transfer fixture for shaft seal components. The transfer fixture may be formed of a suitable plastic material so that the fixture may be expendable or reusable for the assembly and transfer of seal components. The transfer fixture consists of a two-piece telescoping assembly; namely, a pilot and a sleeve. The diameter of both the pilot and sleeve correspond to the diameters of the unit for which the seal assembly is manufactured, with the pilot provided with a blind hole to receive the end of a shaft onto which the seal assembly is transferred. The sleeve telescopes over the pilot and acts to move the seal assembly onto the shaft.
Another object of the present invention is the provision of a transfer fixture for shaft seals wherein the seal components are assembled on the fixture and easily and smoothly transferred from the fixture into the desired installation. Seal components are installed on the fixture at their approximate working relationship and are maintained at this working relationship during all subsequent handling, including the transfer operation onto a shaft and their assembly into a unit to be sealed.
A further object of the present invention is the provision of a transfer fixture for a shaft seal where the fixture aids in providing a precise fit and protecting the primary leak paths. The entrance of any foreign material, such as microscopic specks or finger smudges, is prevented as the leak paths are protected from immediately after manufacture and assembly and until installation into the mechanism to be sealed due to the preassembly of the seal components onto the transfer fixture. Additionally, the concentricity relationship of the seal assembly is maintained at all times during installation.
Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly and operation, and such further objects, advantages and capabilities as will later more fully appear and are inherently possessed thereby.